Mouthwash.

[Mortal Coil]

Mods, I wasn't sure where to put this, so feel free to move me wherever.

Whenever I use mouthwash, even if I clean up really well afterwards, I can't stop ants from swarming the place. Any suggestions/tips?

[Sonic Boom]

You mean the basin area? Try rinse the basin with boiling water after cleaning it. Then dry it properly afterwards.

Otherwise use a sterilising- type mouthwash, and not a flavoured one.